Granisetron Hydrochloride Oral Suspension
Granisetron Hydrochloride Oral Suspension contains NLT 90.0% and NMT 110.0% of the labeled content of granisetron hydrochloride (C18H24N4O·HCl). Prepare Granisetron Hydrochloride Oral Suspension (0.056 mg/mL) equivalent to 0.05 mg of Granisetron per mL as follows (see Pharmaceutical Compounding—Nonsterile Preparations 795).
Granisetron (as Hydrochloride) 5 mg (5.6 mg)
Vehicle: A mixture of Vehicle for Oral Solution, NF, and Vehicle for Oral Suspension, NF, (1:1), a sufficient quantity to make 100 mL
Calculate the required quantity of each ingredient for the total amount to be prepared. If using tablets, place the required number of tablets in a suitable mortar, and comminute the tablets to a fine powder with a pestle, or add Granisetron Hydrochloride powder. Add the Vehicle in small portions, and triturate to make a smooth paste. Add increasing volumes of the Vehicle to make a Granisetron Hydrochloride suspension that is pourable. Transfer the contents of the mortar, stepwise and quantitatively, to a calibrated bottle. Add enough Vehicle to bring to final volume, and mix well.
•  Procedure
Mobile phase:  Acetonitrile and 50 mM monobasic sodium dihydrogen phosphate (3:17). Adjust with phosphoric acid to a pH of 7.0. Make adjustments if necessary (see Chromatography 621, System Suitability.)
Standard stock solution:  1.0 mg/mL USP Granisetron Hydrochloride RS
Standard solution:  Transfer 2.5 mL of Standard stock solution to a 100-mL volumetric flask, and dilute with Mobile phase to volume to obtain a solution containing 25 µg/mL of granisetron hydrochloride.
Sample solution:  Shake the Oral Suspension thoroughly by hand. Pipet 5.0 mL into a 10-mL volumetric flask. Dilute with Mobile phase to volume, and mix to obtain a nominal concentration of 25 µg of granisetron hydrochloride/mL.
Chromatographic system 
Mode:  LC
Detector:  UV 300 nm
Column:  4.6-mm × 15-cm; 5-µm packing L10
Flow rate:  1.0 mL/min
Injection size:  20 µL
System suitability 
Sample:  Standard solution
[Note—The retention time of the granisetron peak is 7.0 min. ]
Suitability requirements 
Relative standard deviation:  NMT 2.0% for the replicate injections
Samples:  Standard solution and Sample solution
Calculate the percentage of the labeled amount of C18H24N4O·HCl in the volume of Oral Suspension taken:
Result = (rU/rS) × (CS/CU) × 100
rU== peak response from the Sample solution
rS== peak response from the Standard solution
CS== concentration of granisetron hydrochloride in the Standard solution (µg/mL)
CU== nominal concentration of granisetron hydrochloride in the Sample solution (µg/mL)
Acceptance criteria:  90.0%–110.0%
•  pH 791: 4.0–4.5
•  Packaging and Storage: Package in tight, light-resistant containers. Store at controlled room temperature or controlled cold temperature.
•  Labeling: Label it to state that it is to be well shaken before use, and to state the Beyond-Use Date.
•  Beyond-Use Date: NMT 90 days after the date on which it was compounded when stored at controlled room temperature or when stored at controlled cold temperature
•  USP Reference Standards 11
USP Granisetron Hydrochloride RS
Auxiliary Information— Please check for your question in the FAQs before contacting USP.
Topic/Question Contact Expert Committee
Monograph Jeanne H. Sun
Assistant Scientific Liaison
(CMP2010) Compounding
Reference Standards RS Technical Services
USP35–NF30 Page 3375
Pharmacopeial Forum: Volume No. 34(6) Page 1454